Fleas can live up to eight days on short-haired animals and even longer on animals with long hair. When adult fleas have no host to feed upon, they can survive from a few days to a couple of weeks.
Flea larvae eat the excrement of adult fleas and cannot survive in its absence. Female fleas begin to lay eggs within 48 hours of a first meal of blood, and within four to nine days, they begin to produce around 27 eggs daily and can take in as much as 15 times their body weight each day in blood. Adult fleas can remain dormant for up to five months in a flea-ridden apartment or home and then resurge when people move in, making flea infestations difficult to defeat.